KR20180022695A - Halogenated graphene nanofibers, and their manufacture and use - Google Patents

Abstract

(I) a graphene layer in which no element or component other than sp2 carbon is present, and (ii) a substantially defect-free graphene layer, except for the carbon atoms forming the periphery of the graphene layer of the nano- And a halogenated graphene nanofibrous body is described which is about 5% by weight or less based on the total weight of the nano plate body when the total content of halogen in the nano plate body is calculated as bromine. Methods for making such nano-plates and various end-uses for such nano-plates are also described. Also provided is a process for producing halogenated exfoliated graphite having a total halogen content of about 5 wt.% Or less based on the total weight of halogenated exfoliated graphite, calculated as bromine, and halogenated exfoliated graphite.

Description

Halogenated graphene nanofibers, and their manufacture and use

The present invention relates to novel halogenated graphene nanoplatelets, novel process technologies for producing halogenated graphene nanofibers, and to the use of such halogenated graphene nanofibers with excellent properties, .

The graphene nano plate is a nanoparticle composed of a layer of graphene having a platelet shape. The graphene nanofabric is considered a desirable alternative to carbon nanotubes for use in similar applications.

There are two main production methods of graphene nanofibers known in the art, namely a 'bottom up' method and a 'top down' method. The bottom-up method is a method of chemical vapor deposition, Which is time-consuming and expensive. Another method, the top-down method, is disclosed in conjunction with natural or synthetic graphite to form several laminated layers in several layers or one layer Various processes are used to separate the particles into layered particles of some general type, including peeling ("scotch tape"), liquid phase exfoliation, and intercalation / Intercalation / exfoliation is a step-wise process of intercalating material into graphite and vaporizing or decomposing such material from graphite, which causes the graphite layer to expand, Separated and peeled to form a plate. Various materials are used in the art to intercalate graphite.

While several types of graphene nano platelets are commercially available, there is a need for graphene nano platelets with better performance and better properties. The present invention is believed to satisfy this need.

(I) a graphene layer in which no element or component other than sp ² carbon is present, and (ii) a substantially defect-free graphene layer, wherein carbon atoms forming the perimeter of the graphene layer of the nano- Characterized in that the halogenated graphene nanofabric body has an element graphene layer and the halogen content is in the range of about 5 wt% or less, based on the total weight of the nanofabric body, Lt; / RTI > The present invention also provides a halogenated exfoliated graphite, wherein the total content of halogen in the exfoliated graphite is calculated as bromine, and up to about 5 wt%, based on the total weight of the halogenated exfoliated graphite.

In a preferred embodiment, the halogenated graphene nanofabric is a halogenated graphene nanofibrous body having a halogen chemically bonded around the graphene layer of the nanofabric.

In another preferred embodiment, the halogenated graphene nanofabric is a brominated graphene nanofibrous body having bromine chemically bonded around the graphene layer of the nanofabric.

The halogenated graphene nanofibers also have chemically bonded oxygen impurities with high purity and very little or no detectable. Accordingly, the halogenated graphene nanofibers obtainable according to the present invention qualify for the description or classification of "pristine ". In addition, there is practically no structural defects in the halogenated graphene nanofibers of the present invention. This may be due, at least in part, to the distinct uniformity and structural integrity of the sp ² graphene layer of the halogenated graphene nanofabric of the present invention. Among the additional advantageous properties of these nanoplates are their excellent electrical conductivity and good physical properties as compared to commercially available halogen-containing graphene nanofibers. In addition, no solvent is required during the synthesis of the halogenated graphene nanoparticles of the present invention, and an intermediate step of forming graphitic oxide to form the halogenated graphene nanoparticles of the present invention is not required .

Novel synthetic process technology is also provided by the present invention. Thus, in one of its process embodiments, the present invention provides a continuous process for the production of a halogenated graphene sheet. Advantageously, the process techniques described herein for producing halogenated graphene nanofibers are believed to be reproducible and can be performed on a commercial scale.

Accordingly, the present invention provides, in one of its embodiments, a halogenated graphene nanofibrous body having no elements or components other than sp ² carbon other than the carbon atoms forming the periphery of the graphene layer of the nano- ≪ / RTI > As is well known, this is the first time that such halogenated nanofabric bodies are formed by any process. It is believed that the absence of defects can be attributed at least in part to the high purity of the halogenated nano-plates of the present invention, in which essentially no oxygen or other elements are present except for the halogen (s) used in the preparation thereof. Among these halogenated graphene nano-plates, a preferred nano-plate is a brominated graphene nano-plate, that is, a nano plate formed by using a bromine element (Br ₂ ) as a halogen source.

As described below, a two-layer brominated graphene nanoparticle was obtained and found to have only or nearly only sp ² carbon except for the carbon atoms forming the periphery of the graphene layer. Such two-layered brominated graphene nanofabric bodies exhibit better conductivity, better physical properties, and other highly desirable characteristics as compared to commercially available nanofabric bodies.

These and other embodiments and features of the present invention will become more apparent from the following description, drawings, and appended claims.

1 is a high-resolution transmission electron microscopy (TEM) image of a portion of a brominated graphene nanofibrous body of the present invention.
Figure 2 is a set of X-ray powder diffraction patterns for a series of bromine-intercalated graphite formed in the process of the present invention, and an X-ray powder diffraction pattern for graphite.
3 is a high-resolution transmission electron microscopy (TEM) image of the two-layer brominated graphene nanofibers of the present invention.
4A is a photograph of brominated peeled graphite formed by the method of the present invention dispersed in water. Figure 4b is a photograph of graphite on a water surface.
FIG. 5 is a graph of the thermogravimetric analysis (TGA) results in nitrogen for the brominated exfoliated graphite formed by the method of the present invention and the comparison results for natural graphite.
FIG. 6 is a graph of thermogravimetric analysis (TGA) results in air for graphite graphene nanoparticles formed by the method of the present invention, and comparison results for graphite starting materials.

As is known in the art, and as used throughout this document, the term "intercalation " refers to the inclusion of material between layers of graphite. The terms "intercalating agent" and "intercalant" are used interchangeably throughout this document. As used throughout this document, and as is known in the art, the term "exfoliation " means removing material present between the layers of graphite and increasing the separation of the graphite layer.

"Pristine or almost pristine" means that no observable damage is present or that any damage to the graphene layer as shown by high resolution transmission electron microscopy (TEM) or by atomic force microscopy (AFM) If present, this impairment is negligible, meaning that it is not meaningful that it is not worth considering. For example, any such damage does not have an unobservable deleterious effect on the nanoelectronic nature of the halogenated graphene nanofabric. In general, any damage in the halogenated graphene nanofabric arises from damage present in the graphite making up the halogenated graphene nanofabric, and any damage and / or impurities from the graphite starting material may result in product halogenation The graphene remaining on the nano plate.

In the practice of the present invention, the intercalating agent is a divalent halogen molecule. The term "divalent halogen molecule" and "divalent halogen " used throughout this document include elemental halogen compounds and divalent interhalogen compounds.

Throughout this document, Br ₂ is sometimes referred to as "elemental bromine" and F ₂ is sometimes referred to as "elemental fluorine".

Binary halide molecules for use in forming the halogenated graphene nanofibers of the present invention are generally selected from the group consisting of bromine element (Br ₂ ), fluorine element (F ₂ ), iodine monochloride (ICl), iodine monobromide (IBr) , Iodine monofluoride (IF), or a mixture of any two or more of these halogen compounds. Bromine (Br ₂₎ is a preferred diatomic halogen molecules.

The term "halogenated" in the halogenated graphene nanofibers used throughout this document refers to a mixture of Br ₂ , F ₂ , ICl, IBr, IF, or any combination thereof used to prepare graphene nanofibers It refers to the graphene nano plateau. Similarly, in the case of halogenated exfoliated graphite, the term " halogenated "refers to exfoliated graphite used to produce exfoliated graphite with Br ₂ , F ₂ , ICl, IBr, IF, or any combination thereof.

The halogenated exfoliated graphite is an embodiment of the present invention and can be obtained by the method of the present invention. Brominated peeled graphite is the preferred halogenated peeled graphite.

The halogenated graphene nanofibrous body is an embodiment of the present invention and can be obtained by the method of the present invention. The brominated graphene nanofibers are the preferred halogenated graphene nanofibers.

The halogenated graphene nanofabric member of the present invention includes a graphene layer, and includes, except for the carbon atoms forming the periphery of the graphene layer of the nano plate, (i) no element or component other than sp ² carbon Graphene layer, and (ii) a substantially defect-free graphene layer. The total content of halogen in the halogenated graphene nanofabric is calculated as bromine and is about 5 weight percent or less based on the total weight of the halogenated graphene nanofabric.

The phrase "no element or component other than sp ² carbon" means that the impurity is usually less than one part per million (parts per million) weight / weight, based on the total weight of the nano- It is instructive. Typically, the halogenated graphene nanofibers have up to about 3 weight percent oxygen, preferably up to about 1 weight percent oxygen; The oxygen observed in the halogenated graphene nanofibers is believed to be impurities originating from the graphite starting material.

The phrase " substantially defect-free "indicates that the graphene layer of the halogenated graphene nanofabric body is substantially free of structural defects including holes, five-membered rings, and seven-membered rings.

In some embodiments, the halogenated graphene nanofibers of the present invention comprise a halogen chemically bonded around the graphene layer of the nanofabric. Halogen atoms that can be chemically bonded around the graphene layer of the halogenated graphene nanofibers include fluorine, chlorine, bromine, iodine, and mixtures thereof, with bromine being preferred.

Although the total amount of halogens present in the nanoparticles of the present invention can vary, the total content of halogens in the nanoparticles is less than about 5 wt%, preferably less than about 0.001 wt%, based on the total weight of the nanoparticles, To about 5% by weight bromine (or when calculated as bromine), which is determined by the amount or atomic weight of the particular binary halogen composition used. More preferably, the total content of halogens in the nano plate is in the same range as the total brom content in the range of about 0.01 wt.% To about 4 wt.%, Based on the total weight of the bromine nanoplate. In some embodiments, the total content of halogen in the nanofabric is preferably from about 0.001 wt% to about 5 wt% bromine, more preferably from about 0.01 wt% to about 5 wt%, based on the total weight of the nanofabric, Is in the same range as the total bromine content in the range of 4 wt% bromine.

The total amount of halogens present in the halogenated exfoliated graphite of the present invention may be different and may be up to about 5 weight percent, preferably about 0.001 weight percent, when calculated as bromine, based on the total weight of the halogenated exfoliated graphite. (Or calculated as bromine) in the range of from about 0.01 wt.% To about 5 wt.%, More preferably in the range of from about 0.01 wt.% To about 4 wt.%, Or preferably the total weight of the halogenated exfoliated graphite Based on the total halogen content, calculated as bromine, preferably has a total halogen content in the range of about 0.001 wt% to about 5 wt%, more preferably in the range of about 0.01 wt% to about 4 wt%.

As used herein, the phrases " as bromine ", "reported as bromine "," calculated as bromine ", and similar phrases for halogen refer to the amount of halogen, unless otherwise noted, . For example, although the fluorine element can be used, the amount of halogen in the halogenated exfoliated graphite and the halogenated graphene nanofabric is described as a value for bromine.

In a preferred embodiment of the present invention, the halogenated, especially brominated, nano-platelets comprise a few-layered graphene. By "water layer graphene" is meant that the grouping of laminated layered graphene nanofabrices contains up to about 10 graphene layers, preferably about 1 to about 5 graphene layers. Such water-soluble graphenes typically have superior properties compared to corresponding nanofabric sheets of a greater number of graphene layers. Particularly preferred is a halogenated graphene nanofabric material comprising two-layer graphene, in particular a graphene nanofibrous material with two-layer brominated graphene.

A particularly preferred halogenated graphene nanofibrous body is a brominated graphene nanofibrous body comprising a multi-layer or two-layer brominated graphene nanofibrous body wherein the distance between the layers is measured by high resolution transmission electron microscopy (TEM) , It is about 0.335 nm. Particularly preferred is a brominated graphene nanofibrous layer comprising a two-layer graphene whose thickness is about 0.7 nm when the thickness of the two layers is measured by atomic force microscopy (AFM).

In addition, the halogenated graphene nanofibers of the present invention often have a particle size of from about 0.1 to about 50 microns, preferably from about 0.5 to about 50 microns, more preferably from about 1 to about 50 microns, as measured by atomic force microscopy (AFM) And has a lateral dimension in the range of about 40 microns. In some applications, lateral dimensions of about 1 to about 20 microns are preferred for the halogenated graphene nanofibers. For halogenated graphene nanofibers, larger lateral dimensions often provide better conductivity and increased physical or mechanical strength. The lateral dimension is the linear size of the halogenated graphene nanofibers perpendicular to the layer thickness.

The halogenated graphene nanoparticles of the present invention, particularly the brominated graphene nanoparticles, have improved water dispersibility. It is theorized that this property is provided by chemically bonded halogens around the graphene layer of the nano plate.

Another advantageous characteristic of the halogenated graphene nanoparticles of the present invention, particularly the brominated graphene nanofibers, is excellent thermal stability. In particular, brominated graphene nanofibers exhibit negligible weight loss when subjected to thermogravimetric analysis (TGA) at temperatures below about 800 ° C under an inert atmosphere. At 900 DEG C under an inert atmosphere, the TGA weight loss of the grafted graphene nanofibers is typically about 4 weight percent or less, usually about 3 weight percent or less. Further, in the present invention, it has been observed that the TGA weight loss temperature of the brominated graphene nanofibers under an inert atmosphere decreases as the amount of bromine increases. The inert atmosphere may be, for example, helium, argon, or nitrogen. Nitrogen is commonly used and is preferred.

A preferred embodiment of the present invention is a process for the preparation of a thermogravimetric analysis (TGA) which, under negligible nitrogen atmosphere described herein, has negligible weight loss when subjected to a thermogravimetric analysis (TGA) Or a brominated graphene nanofibrous body containing two layers of graphene nanofabric. Preferably, the TGA weight loss of the brominated graphene nanofibers is less than or equal to about 4 weight percent at 900 DEG C, more preferably less than or equal to about 3 weight percent at 900 DEG C under an inert atmosphere, under an inert atmosphere.

The halogenated exfoliated graphite is believed to consist of agglomerated and / or laminated layers of halogenated graphene nanofabric. In halogenated exfoliated graphite, the halogen content and its preference are the same as those described for the halogenated graphene nanofibers, except that the total weight is of halogenated exfoliated graphite.

The process of the invention for producing halogenated exfoliated graphite and part of the process for producing halogenated graphene nanofibers is carried out in the absence of water and oxygen. In this method,

I) Dyes selected from bromine element (Br ₂ ), fluorine element (F ₂ ), iodine monochloride (ICl), iodine monobromide (IBr), iodine monofluoride (IF), and mixtures of any two or more thereof Contacting the halogen with a graphite flake to form a solid comprising halogen-intercalated graphite; And

II) reacting the halogen-intercalated graphite to a temperature of at least about 400 ° C and keeping the halogen-intercalated graphite at such temperature, and (b) reacting Br ₂ , F ₂ , Halogen-intercalated graphite in the absence of oxygen and water vapor, while maintaining contact of the binary halide and the halogen-intercalated graphite selected from the group consisting of ICI, IBr, IF, or mixtures of any two or more thereof. And withdrawing the halogenated exfoliated graphite from the reaction zone, wherein the halogenated exfoliated graphite has a total halogen content of about 5% by weight or less;

III) optionally, repeating step I) and step II) one or more times in order;

IV) optionally, treating the halogenated exfoliated graphite with a halogenated graphene nanoplate lassification procedure to form a halogenated graphene nanoplate;

V) When step IV) is carried out, it comprises repeating step I), step II) and, optionally, step IV) one or more times in order.

When the halogenated exfoliated graphite is the desired product, a halogenated graphene nanofabric glass procedure is performed.

The method may be carried out as a batch process or as a continuous process. When carried out as a continuous process, the supply of halogen-intercalated graphite is preferably continuous, and preferably the withdrawal of the halogenated exfoliated graphite from the reaction zone leads to a continuous supply of halogen-intercalated graphite to the reaction zone . When the supply is continuous, some interruption during the supply is acceptable, but the downtime is small enough not to cause material failure in the reaction.

Typically, the environment in which step I) and step II) of the method of the present invention is carried out is a water-free, oxygen-free environment. The moisture-free, oxygen-free environment can be obtained by purging the vessel and reaction zone before use with argon, helium, or, preferably, an inert gas such as nitrogen. In some cases, an inert gas (argon, helium, or preferably nitrogen) can be used as the carrier gas. Trace amounts of oxygen and water (parts per hundred parts) can be tolerated during the process of the present invention. Step IV) of the method need not be performed in a moisture-free, oxygen-free environment.

As used throughout this document, the term "reaction zone" refers to a zone in which halogen-intercalated graphite is maintained at about 400 ° C or higher. Step II) of the process may be carried out in any reactor (reaction zone) which allows rapid heating of the halogen-intercalated graphite fed to the reactor, such as a tubular reactor, for example a drop reactor .

In the practice of the present invention, the graphite starting material is usually in the form of a powder, or preferably a flake. Certain types of graphite (powders, flakes, etc.) and sources of graphite (natural or synthetic) do not appear to affect the results obtained. Graphite has an average particle size of about 50 microns (about 270 standard U.S. mesh) or more. Preferably, the graphite has an average particle size of at least about 100 [mu] m (about 140 standard U.S. mesh). More preferably, the graphite has an average particle size of at least about 200 microns (about 70 standard U.S. mesh), and even more preferably, at least about 250 microns (about 60 standard U.S. mesh). Graphite having a larger average particle size allows a larger amount of binary halogens to be intercalated into graphite (as compared to a smaller size graphite flake), resulting in easier peeling and less product Was obtained. It has also been found that graphite having an average particle size of about 20 mu m or less is not clearly expanded when it is carried out by the method of the present invention. Defects and / or impurities in the graphite starting material remain in the product halogenated exfoliated graphite and the halogenated graphene nanofibers.

Expanded graphite is a commercially available product, the result of a set of intercalation and exfoliation steps, and may contain some oxygen from its production process. Commercially available expanded graphite may be used in the process of the present invention.

In the process of the present invention, the divalent halogen molecule is usually a bromine atom (Br ₂ ), a fluorine element (F ₂ ), iodine monochloride (ICl), iodine monobromide (IBr), iodine monofluoride And mixtures of any two or more thereof. The bromine element (Br ₂ ) is preferred as the divalent halogen in this way. When the divalent halogen is IF, step I) is usually carried out at low temperature, generally below room temperature.

Step I) of the process is carried out by contacting graphite and binary halogen (s). In the practice of the present invention, binary halogens can be used in gaseous form or liquid form. Divalent halogens can be supplied as a gas or as a solid or liquid which is subsequently vaporized to provide a gaseous form. Step I) is carried out in the absence of water and oxygen. The temperature during step I) is usually ambient (about 18 [deg.] C to about 25 [deg.] C).

In a preferred embodiment of step I), the graphite is disposed in a fluidized bed, and the binary halogen gas flows through the fluidized bed of graphite to form halogen-intercalated graphite.

In step II), the stripping and halogenation of the halogen-intercalated graphite takes place to form halogenated exfoliated graphite. The divalent halogen gas present in step II) is usually provided by stripping of halogen-intercalated graphite. Step II) is carried out in the absence of water and oxygen.

The halogenated exfoliated graphite is rapidly heated to above 400 DEG C by heating the reaction zone at about 400 DEG C or higher and / or by heating the halogenated exfoliated graphite in step II), and is maintained at 400 DEG C or higher. The heating in step II) includes methods such as conduction, convection, and exposure of halogen-intercalated graphite to radiation (e.g., infrared or microwave), or any combination thereof. In step II) the heating is preferably at least about 2 ° C / second, more preferably at least about 50 ° C / second, even more preferably at least about 100 ° C / second and even more preferably at least about 250 ° C / Speed. Preferably, the heating rate is from about 2 DEG C / sec to about 1000 DEG C / sec, more preferably from about 50 DEG C / sec to about 1000 DEG C / sec, and even more preferably from about 250 DEG C / Range.

In step II), the residence time is generally in the range of from about 1 second to about 5 hours, or from about 1 second to about 60 seconds, or from about 0.1 minute to about 2 hours, or from about 1 hour to about 5 hours. A shorter residence time is desirable for faster heating rates, and longer residence times are desirable for slower heating rates.

When step I) and step II) are repeated, preferably, a total of three sets of steps I) and II) are carried out on graphite (two additional sets of steps I and II). If more (or less) sets of steps I) and II) are desired. It is preferred that a total of three sets of steps I), II) and IV) are carried out on graphite when the set of step I), step II) and step IV) are repeated one or more times in order Additional sets of Stage I, Stage II, and Stage IV). More (or less) sets of steps I), II) and IV) may be desired. Optionally, step I) and step II) can be repeated one or more times after step IV), or only a combination of step I) and step II) and repeating step I), step II), and step IV) .

A convenient way to transport particles, such as graphite, halogen-intercalated graphite, halogenated exfoliated graphite, and / or halogenated graphene nanofibers, is by blowing this to the desired location. A useful device for separating binary halogen (s) from solid particles such as graphite, halogen-intercalated graphite, halogenated exfoliated graphite, and / or halogenated graphene nanofibers is cyclone.

The pressure conditions for step I) and step II) are typically ambient or superatmospheric pressure, and the process may also be carried out under reduced pressure or under vacuum. The atmospheric excess pressure is preferably between about 15 psi (1 x 10 ⁵ Pa) and about 1000 psi (6.9 x 10 ⁶ Pa), more preferably between about 20 psi (1.4 x 10 ⁵ Pa) and about 100 psi 10 ⁵ Pa). In one embodiment of the present invention, the graphite is dried under reduced pressure, for example, at a pressure of about 5 torr (6.6 x 10 ² Pa) to about 700 torr (9.3 x 10 ⁴ Pa), more preferably about 10 torr ³ Pa) to about 600 torr (8 x 10 < ⁴ > Pa).

At ambient pressure, the temperature in the reaction zone in step II) is typically at least about 400 ° C, preferably from about 400 ° C to about 1200 ° C, more preferably from about 600 ° C to about 1100 ° C, Deg.] C to about 1000 [deg.] C. When step II) is carried out under reduced pressure, lower temperatures can be used. Generally, the temperature in the reaction zone is less than about 3000 ° C.

When forming a halogenated graphene nano plate, the halogenated exfoliated graphite is carried out in a halogenated graphene nanofiltrel glass procedure, which is typically one or more particle size reduction techniques, using one or more particle size reduction techniques Techniques can be combined. Particle size reduction techniques include, but are not limited to, grinding, dry or wet milling, high shear mixing, and ultrasonication. When grinding or milling and ultrasonic treatment are carried out on a halogenated graphene nanofabric body, grinding or milling is preferably carried out before ultrasonic treatment. Solvents for ultrasonic treatment are typically one or more polar single proton solvents. Suitable solvents for ultrasonic treatment include N-methyl-2-pyrrolidinone, dimethylformamide, acetonitrile, and the like. Indeed, optionally and preferably, even water containing a surfactant can be used in the ultrasonic treatment step. One or more ionic and / or nonionic surfactants may be used. Suitable surfactants are known in the art. Conventional separation techniques can be used (e. G., Filtration or centrifugation) to separate the ultrasonically treated halogenated graphene nanofibers from the solvent.

It is not necessary to maintain the halogenated exfoliated graphite or the halogenated graphene nanofibers in a water-and / or oxygen-free environment.

At the end of the process, the halogenated exfoliated graphite, when desired, at the end of the process, if desired, the halogenated exfoliated graphite, or the halogenated graphene nanoplanar body, is usually a slurry, a wet cake, And collected in powder form. When in powder form, halogenated exfoliated graphite or halogenated graphene nanofibers can be collected by a filter or other particle collection device.

The binary halide gas released from the halogen-intercalated graphite during the process can be removed from the reaction zone after step II) of the process. If desired, the quaternary halogen gas released during the process is recovered and optionally recycled in this manner.

As noted above, with reference to the figures, Figure 1 is a high-resolution transmission electron microscopy (TEM) image of a portion of a brominated graphene nano plate of the present invention, which TEM image shows the brominated 0.0 > a < / RTI > large lateral dimension of the graphene nano plateau.

In FIG. 2 , a set of X-ray powder diffraction patterns for a series of bromine-intercalated graphite formed in the process of the present invention and a pattern for graphite are shown. In this series, as the amount of elemental bromine increased, a fixed amount of graphite was reacted / contacted. The pattern is arranged from the smallest to the greatest amount of bromine, from top to bottom, the second result, the end result is for graphite. The product in which the X-ray diffraction pattern is depicted is the bromine-intercalated graphite produced as in step I) of the process of the present invention (see also Example 2 below).

In Figure 3 , a high resolution transmission electron microscope (TEM) image shows two layers of the inventive two-layer brominated graphene nanofabric as two parallel ridges or lines in the image. The distance between the two layers was determined to be about 0.335 nm. [Refer to Embodiment 2].

Figures 4A and 4B are top views. Figure 4a, the water separation brominated graphite and Figure 4b, graphite and water, the comparison sample of Figure 4a, due to the dispersion of the water separation brominated graphite, and has a rugged texture (lumpy texture). Conversely, the sample of Figure 4B has a smooth texture because graphite is on the surface of the water. Halogenated exfoliated graphite (e. G., Brominated exfoliated graphite) is the product of step II) of the process of the present invention. [See also Example 2 below].

In FIG. 5 , TGA under N ₂ for brominated exfoliated graphite has very desirable thermal properties. A comparison of the TGA results for brominated exfoliated graphite and the results for graphite shows that the brominated exfoliated graphite has thermal behavior similar to that of graphite. The brominated exfoliated graphite in FIG. 5 is prepared as in step I), step II) and step III) of the process of the present invention (see also example 2 below).

Figure 6 shows that the TGA weight loss in air for the brominated graphene nanofabric is similar to the TGA weight loss in air for the graphite starting material (see Example 2, below).

In this regard, for the brominated graphene nanofibers of the present invention, the dispersibility and thermal behavior are expected to be very similar to the TGA results and water dispersibility identified for the brominated exfoliated graphite. In other words, it is expected that halogenated graphene glass procedures, such as in step IV) of the process of the present invention, will not affect water dispersibility or thermal behavior.

Due to its improved performance capabilities, the halogenated graphene nanofibers of the present invention can be used in small scale (e.g., lithium ion battery anode applications, including telephones and automotive batteries) or in large scales For energy storage applications, or for energy storage devices such as batteries and capacitors. In this regard, it is reasonable to suggest that the halogenated graphene nanofibers provided by the present invention may be used in a variety of energy storage applications under development. Examples of such energy storage applications include silicon anodes, solid state electrolytes, magnesium ion batteries, sodium ion batteries, lithium sulfur batteries, lithium air batteries, and lithium ion capacitor devices. One or more of these devices may be considered to be able to outperform lithium-ion technology.

In some embodiments of the present invention, an energy storage device is provided that includes an electrode comprising a halogenated graphene nanoplate of the present invention, preferably a brominated graphene nanoplate. The electrode may be an anode or a cathode. When the electrode is the anode, it may be a silicon anode. Electrodes containing halogenated graphene nanofibers may be present in lithium ion batteries, lithium sulfur batteries, lithium ion capacitors, supercapacitors, sodium ion batteries, or magnesium ion batteries.

In some embodiments, the electrode is an anode or cathode containing carbon black (at the anode, the active material; at the cathode, the additive), wherein the halogenated graphene nanofabric is in the anode or cathode, based on the total weight of the carbon black , At least about 0.1 weight percent of the carbon black in the anode or cathode. Preferably, the anode comprises about 0.1 wt.% To about 98 wt.% Halogenated graphene nanofabric, more preferably, the halogenated graphene nanofibrous body is a brominated graphene nanofibrous body.

In another embodiment, an electrode containing a halogenated graphene nanofibrous body further comprises one or more of the following:

At least one material selected from carbon, silicon, and / or one or more silicon oxides;

bookbinder;

Conductive aids;

Carbon black; And

The whole house.

Preferably, the electrode is an anode, and more preferably, the halogenated graphene nanofabric is a brominated graphene nanofibrous body. In addition, a halogenated graphene nanofabric body in an amount of about 0.1% by weight or more is preferable for the electrode. In this embodiment, the anode preferably comprises a binder. Typical binders include styrene butadiene rubber and polyvinylidene fluoride (PVDF; also referred to as polyvinylidene difluoride). In a preferred embodiment of such an anode, the improvement comprises a halogenated graphene nanofabric, preferably a brominated graphene nanofibrous, and comprises from about 10% to about 100% by weight of a conductive auxiliary and / or Instead of carbon black, the improvement may include a halogenated graphene nanoplanar body, preferably having a brominated graphene nanoplanar body, wherein at least about 1 weight percent of carbon, silicon, and / or one or more silicon oxides are substituted for do.

As used in connection with energy storage devices, the term "carbon" as used throughout this document refers to natural graphite, refined natural graphite, synthetic graphite, light carbon, soft carbon, carbon black, or any combination thereof.

In some energy storage devices, the brominated graphene nanofibers of the present invention may act as current collectors for the electrodes (either the cathode or the anode) and, in other energy storage devices, The upper body may act as a conductive additive in the electrode.

In some thermosetting or thermoplastic compositions, the halogenated graphene nanofibers of the present invention may function as a thermal management additive. In other thermosetting or thermoplastic compositions, the halogenated graphene nanofibers of the present invention may function as a conductive additive. In another thermosetting or thermoplastic composition, the halogenated graphene nanofibers of the present invention may function as a physical property enhancing additive.

The halogenated graphene nanofibers of the present invention may also be useful in a lubricant composition for a variety of applications. In this regard, reference is made to U.S. Patent No. 8,865,113 for a discussion of the disadvantages of conventional elasto-hydrodynamic lubricants and lubricants for polishing and reduction of asperity.

The halogenated graphene nanofibers of the present invention can also be used in catalyst systems wherein the halogenated graphene nanofibers are used as carbocatalysts in metal-free catalysis, in photocatalysis, or as catalyst supports .

The following examples are presented for illustrative purposes and are not intended to limit the scope of the invention.

Sample feature analysis and performance testing

In the experimental work described in the examples, the samples used were analyzed by the following methods to evaluate their physical characterization and performance.

Atomic microscopy (AFM) - AFM instrument used is a Dimension ^® Icon AFM manufactured by ^{ScanAsyst ®, Bruker Corporation (Billerica,} MA) in a mode having a ScanAsyst ^® probe. Its high-resolution camera and XY localization enable fast and efficient sample searching. Samples were dispersed in dimethylformamide (DMF), coated on mica, and then analyzed under AFM.

High resolution transmission electron microscopy (TEM) - JEM-2100 LaB6 TEM (JEOL USA, Peabody, MA) was used. The operating parameters include an acceleration voltage of 200 kV for imaging, and Energy Dispersive Spectroscopy (EDS) for TEM (Oxford Instruments plc, United Kingdom) for elemental analysis. Samples were first dispersed in dimethylformamide (DMF) and coated on a copper grid.

Scanning Electron Microscopy (SEM) - Electron imaging and elemental microanalysis was performed on a JSM 6300FXV (JEOL USA, Peabody, MA) scanning electron microscope at 5-25 keV. The specimen was coated with a thin layer of gold or carbon before testing. The energy dispersive X-ray spectra were obtained with a low-noise junction field effect transistor and a 5-terminal device with charge recovery mechanism introduced, referred to as PentaFET Si (Li) detector (manufacturer is not clear) It was obtained using a spectrometer equipped with a distributed X- ray, Inca ^® system (Oxford Instruments plc, United Kingdom) - Si (Li) detector with energy. Semi-quantitative concentrations were calculated from the observed intensities. The accuracy of the value is estimated to be plus or minus 20%. All values are percent by weight.

Powder X-ray diffractometer (for XRD) - The sample holder used included a set of silicon-zero background plates on a mount that could be separated by an O-ring sealed polymethylmethacrylate (PMMA) dome . To improve the adhesion, the plate was coated with a very thin film of high vacuum grease (Apiezon ^® ; M & I Materials Ltd., United Kingdom), the powdered sample was rapidly sprayed onto the plate and flattened with a glass slide. The dome and O-ring were installed, and the assembly was moved to the diffraction system. Diffraction data were acquired with Cu kα radiation on a D8 Advance (Bruker Corp., Billerica, MA) equipped with an energy-dispersed one-dimensional detector (LynxEye XE detector; Bruker Corp., Billerica, Repetitive scans were performed over a range of 100 to 140 degrees 2 theta angles with a 0.04 degree step size and a counting time of 0.5 seconds per step. The total time per scan was 8.7 minutes. Peak profile analysis was performed with Jade 9.0 software (Materials Data Incorporated, Livermore, Calif.).

N ₂ -Isootherm - An accelerated surface area and porosity system (Model No. ASAP 2420; Micromeritics Instrument Corporation, Norcross, GA) was used to measure nitrogen adsorption at liquid nitrogen temperatures of 77K. The amount of nitrogen adsorbed was measured according to the applied vapor pressure, which constitutes the adsorption isotherm. The BET (Brunauer-Emmett-Teller) surface area was derived from the nitrogen adsorption isotherm.

GmbH, Germany)가 장착된 동시 DSC/TGA 분석기를 이용하여 수행하였다. 샘플을 120℃에서 20분 동안 사전-건조시키고, 이후에, 질소 또는 공기의 흐름 하에서 10℃/분로 850℃까지 가열하였다. 온도와 함께 잔류 중량을 기록하였다.The TGA-TGA analysis was carried out using an autosampler and silicon carbide (model number STA 449 F3, Netzsch-

GmbH, Germany) using a simultaneous DSC / TGA analyzer. The sample was pre-dried at 120 ° C for 20 minutes and then heated to 850 ° C at 10 ° C / min under nitrogen or air flow. Residual weight with temperature was recorded.

Lithium-Ion Battery Test - A half-cell test was conducted with an electrolyte of a 1 M lithium hexafluorophosphate solution in ethylene carbonate / dimethyl carbonate (LiPF _{6 in} EC / DMC) (50/50) The voltage range tested is 0 to 3V. The anode was prepared as a test sample, as described below, and lithium was used as a counter electrode. Commercial battery-grade graphite was tested as a baseline.

Graphite or 50/50 graphite / brominated graphene nanofibers is mixed with a binder (polyvinylidene fluoride; PVDF) and carbon black in N-methyl-2-pyrrolidone (NMP) , And the obtained paste was coated on a copper foil (having a thickness of about 20 microns) using, for example, a doctor blade available from MTI Corporation, from which a plurality of coin-type batteries of about 2 cm diameter were assembled. The capacities at different charge / discharge ratios were measured using an 8-channel battery analyzer (0.002-1 mA, max. 5V; Model No. BST8-WA, MTI Corporation, Richmond, Calif.).

Supercapacitor test-The supercapacitor test was performed with an electrolyte of 2M lithium bis- (trifluoromethylsulfonyl) imide (LiTFSI) in EC / DMC (50/50) and the tested voltage range was 0 to 2.5V to be. Commercially available powdered activated carbon (PAC) having a surface area of about 800 m < 2 > / g was used as the baseline. Any one of commercial PAC or a mixture of PAC and a brominated graphene nanofibrous substance is mixed with binder polyvinylidene fluoride (PVDF) and carbon black in N-methyl-2-pyrrolidone (NMP) The obtained paste was coated on a copper foil (having a thickness of about 20 microns) using a doctor blade, from which a plurality of coin-shaped battery cells having a diameter of about 2 cm were assembled. The cyclic voltammetry (CV) curve was measured from 0 to 2.5 V with a potentiostat (Model No. SP-150, Bio-Logic Science Instruments SAS, Claix, France) at a scan rate of 20 mV / And the capacitance was calculated from the integration of the 20th discharge curve.

Example 1

A sample of several individual 2 grams of natural graphite (Abbury Carbons, Asbury, New Jersey), 35% of the particles being greater than 300 microns and 85% of the particles being greater than 180 microns, , 0.5 mL, 1 mL, 1.5 mL, or 3 mL of liquid bromine (Br ₂ ). After 24 hours, the color from the bromine vapor in the vial became more dense as the bromine vapor concentration in the vial increased. The resulting bromine-intercalated material was analyzed by X-ray powder diffraction (XRD). As shown in Figure 2, different bromine-intercalated compounds were formed, depending on the amount of bromine vapor that was visually observable. As indicated by the presence of liquid bromine, "Stage-2" bromine-intercalated graphite was formed immediately after the bromine vapor reached saturation. In the intercalation step of all of the other examples of this embodiment, the saturated bromine vapor pressure was maintained during the intercalation step to obtain stage-2 bromine-intercalated graphite, except when otherwise specifically stated.

Example 2

Natural graphite (4 g) of the same particle size as used in Example 1 was contacted with 4 g of liquid bromine at room temperature for 64 hours. Excess liquid bromine was present to ensure the formation of stage-2 bromine-intercalated graphite. All stage-2 bromine-intercalated graphite was continuously fed to a drop tube reactor (diameter 5 cm) pre-purged with nitrogen for a period of 45 minutes while the reactor was maintained at 900 < 0 & Respectively. The bromine vapor pressure was maintained in the drop reactor for 60 minutes while maintaining the temperature of the reactor at 900 占 폚. The solid material in the reactor was cooled with a stream of nitrogen.

Some cooled solid material (3 g) was contacted with liquid bromine (4 g) at room temperature for 16 hours and an excess of liquid bromine was present to ensure formation of stage-2 bromine-intercalated graphite . Subsequently, all such stage-2 bromine-intercalated graphite was continuously fed into a nitrogen pre-purged drop tube reactor (diameter 5 cm) within 30 minutes. The reactor was maintained at 900 占 폚 during the supply of stage-2 bromine-intercalated graphite. The bromine vapor pressure was maintained in the drop reactor for 60 minutes while maintaining the temperature of the reactor at 900 占 폚. The solid material in the reactor was cooled with a nitrogen stream.

Some cooled solid material (2 g) obtained immediately was contacted with liquid bromine (2.5 g) at room temperature for 16 hours and excess liquid bromine was added to ensure the formation of stage-2 bromine-intercalated graphite . Subsequently, all such stage-2 bromine-intercalated graphite was continuously fed into a nitrogen pre-purged drop tube reactor (diameter 5 cm) within 20 minutes. The reactor was maintained at 900 占 폚 during the supply of stage-2 bromine-intercalated graphite. The bromine vapor pressure was maintained in the drop reactor for 60 minutes while maintaining the temperature of the reactor at 900 占 폚. The solid material in the reactor was cooled with a nitrogen stream.

Some cold solids obtained immediately were dispersed in dimethylformamide (DMF), sonicated for 6 minutes, and then analyzed by TEM and AFM. The TEM results indicated that the brominated graphene nanofibers contained two layers of graphene and the TEM analysis also showed that the distance between two graphene layers (d002) was about 0.335 nm (see Figure 3) , Which means that this graphene layer is damage-free and contains only sp ² carbon in the graphene layer. AFM analysis confirmed that the sample contained two-layer graphene and also showed that the thickness of the two-layer graphene was about 0.7 nm, indicating that the graphene layer is a damage- ² carbon is present.

The EDS analysis showed that 0.9 wt% bromine, as well as 97.7 wt% carbon, 1.3 wt% oxygen, and 0.1 wt% chlorine were present in the sample.

The sample was found to contain a two-layer brominated graphene nanofibrous body with at least lateral dimensions of more than 4 microns, and this sample also had a four-layered brominated graphene nanoplate with a lateral dimension of about 9 microns The upper body was contained.

Rather than being treated by ultrasonic treatment, some cooled solid material from the third set of intercalation and stripping steps was performed with TGA under air. The weight loss of the sample up to 800 DEG C was less than about 1%. Some graphite starting materials were also analyzed by TGA. The weight loss from graphite was also negligible up to 800 ° C in N ₂ . Thus, N ₂ was concluded that the different characteristic properties of the brominated graphene nano platelets present in from a weight loss of up to 800 ℃ negligible invention.

Rather than being treated by ultrasonic treatment, some cooled solid material from the third set of intercalation and stripping steps was performed with TGA under air. The weight loss of the sample was initiated at about 700 ° C. Some graphite starting materials were also analyzed by TGA. Weight loss from graphite was also observed to start in air at about 700 ° C (see FIG. 6).

The cooled solid material (0.2 grams) and graphite (0.2 grams) of the other part from the third set of intercalation and stripping steps were mixed with a separate 250 mL volume of water. The cooled solid material (brominated exfoliated graphite) was readily dispersed in water, and graphite floated on water. These results indicate that the brominated graphene nanofibers of the present invention have improved water dispersibility.

Example 3

Natural graphite (4 g) of the same particle size as used in Example 1 was contacted with 6 g of liquid bromine at room temperature for 48 hours. An excess of liquid bromine was present to ensure the formation of Stage-2 bromine-intercalated graphite. All stage-2 bromine-intercalated graphite was continuously fed into a nitrogen pre-purged drop tube reactor (diameter 5 cm) for a period of 60 minutes while the reactor was maintained at 900 占 폚. The bromine vapor pressure was maintained in the drop reactor for 60 minutes while maintaining the temperature of the reactor at 900 占 폚. The solid material in the reactor was cooled with a stream of nitrogen.

Some cooled solid material (3 g) was contacted with liquid bromine (4.5 g) at room temperature for 16 hours to allow excess liquid bromine to be present to ensure the formation of stage-2 bromine-intercalated graphite. Subsequently, all such Stage-2 bromine-intercalated graphite was continuously fed into a nitrogen pre-purged drop tube reactor (diameter 5 cm) for 30 minutes. The reactor was maintained at 900 DEG C during the feeding of Stage-2 bromine-intercalated graphite. While maintaining the temperature of the reactor at 900 占 폚, the bromine vapor pressure was maintained in the drop reactor for 30 minutes. The solid material in the reactor was cooled with a stream of nitrogen.

Some cooled solid material (2 g) obtained immediately was contacted with liquid bromine (3 g) at room temperature for 24 hours and excess liquid bromine was present to ensure the formation of stage-2 bromine-intercalated graphite . Subsequently, all such Stage-2 bromine-intercalated graphite was continuously fed to a nitrogen pre-purged drop tube reactor (diameter 5 cm) for 20 minutes. The reactor was maintained at 900 DEG C during the feeding of Stage-2 bromine-intercalated graphite. While maintaining the temperature of the reactor at 900 占 폚, the bromine vapor pressure was maintained in the drop reactor for 60 minutes. The solid material in the reactor was cooled with a stream of nitrogen.

Some cooled solid material from the third set of intercalation and stripping steps was analyzed for bromine content by a wet titration method and 2.5% by weight of bromine was present in the sample.

A portion (1 g) of the cooled solid material from the third set of intercalation and stripping steps was mixed with 50 mL of NMP, sonicated, and then filtered to yield a brominated graphene nanoplate Respectively. The filter cake was vacuum dried at 130 DEG C for 12 hours.

Example 4

The brominated graphene nanofibers from Example 3 (0.4 g), graphite (0.4 g), carbon black (0.1 g) and PVDF (0.1 g) were mixed in NMP and coated on a copper foil. Six coin-shaped cells with a diameter of 2 cm were assembled with the anode from this coating on the copper foil for the Li-ion battery test. The battery was initially charged / discharged once at C / 20, charged / discharged at C / 2 for 20 times, and then at 10 C for 500 times. At the 20th cycle, the average capacity of the cell at C / 2 charge / discharge rate is 210 mAh per gram of active material, 262 mAh per gram of brominated graphene nanofabricate, and at a discharge rate of 10 C / Is 64 mAh per gram of active material, and 98 mAh per gram of brominated graphene nanofabric.

Comparative Example 1

Graphite (0.8 g), carbon black (0.1 g), and PVDF (0.1 g) were mixed in NMP and coated on a copper foil. Six coin-shaped cells with a diameter of 2 cm were assembled with the anode from this coating for a Li-ion battery test. This battery was initially charged / discharged once at C / 20, then charged / discharged at C / 2 20 times, and then at 10 C 500 times. The average capacity of the battery at the C / 2 charge / discharge rate is 159 mAh per 1 g of active material (graphite) at the 20th cycle, and the average capacity of the battery is 1 g of the active material (graphite) at the charge / Lt; / RTI >

Example 5

Brominated graphene nanofibers from Example 3 (0.2 g), powdered activated carbon (0.6 g), carbon black (0.1 g) and PVDF (0.1 g) were mixed in NMP and coated on a copper foil . Nine symmetrical coin type cells with a diameter of 2 cm were assembled with both electrodes from this coating for supercapacitor testing. The average capacity of the cell was 46.5 F per gram of active material.

Example 6

Brominated graphene nanofibers from Example 3 (0.1 g), powdered activated carbon (0.8 g), and PVDF (0.1 g) were mixed in NMP and coated onto copper foil. Nine symmetrical coin type cells with a diameter of 2 cm were assembled with both electrodes from this coating for supercapacitor testing. The average capacity of the cell was 63 F per 1 g of active material.

Comparative Example 2

Powdered activated carbon (0.8 g), carbon black (0.1 g), and PVDF (0.1 g) were mixed in NMP and coated on a copper foil. Nine symmetrical coin type cells with a diameter of 2 cm were assembled with both electrodes from this coating for supercapacitor testing. The average capacity of the cell was 53 F per 1 g of active material.

Ingredients referred to by chemical names or chemical formulas in any part of the specification or claims thereof, whether referred to singular or plural, are also intended to include other materials referred to by chemical name or chemical type (e.g., ≪ / RTI > and the like). This is because in any case the chemical changes, changes and / or reactions obtained are natural consequences of linking certain components together under the conditions required in accordance with the present disclosure, such chemical changes, changes and / It does not matter what happens. Accordingly, the components are identified as components that are bound together in connection with performing the desired task or forming the desired composition. Also, although the following claims may refer to materials, components and / or components in their present tense ("include," "is,", etc.), reference is made to the material, component or component , Because the material, component or component first came into contact with one or more other materials, components and / or components in accordance with the present disclosure, and was present at a point in time prior to being blended or mixed. Accordingly, when a substance, component or component is performed according to the general description of the present specification and the chemist, it is possible to lose its original identity through chemical reaction or modification during the course of the contacting, blending or mixing operation Is not a real problem.

The present invention may include, consist, or essentially comprise the materials and / or procedures recited herein.

As used herein, the term "about" as used in the methods of the present invention, or modifying the amount of constituents in the compositions of the present invention, refers to, for example, conventional Through measurement and liquid manipulation procedures, through unintentional errors in this procedure, through the manufacture of the components used to make the composition or perform the method, the difference in source, or purity, etc. Refers to the deviation. The term " about "also includes a different amount due to the different equilibrium conditions for the composition formed from the particular initial mixture. The claims, whether modified or not by the term " about " include equivalents to amounts.

As used herein, the singular forms "a" or "an" as used herein are not intended to be limiting, and should not be construed as limiting, to a single component referred to in the description or the claims . Rather, the singular forms as used herein are intended to include one or more such elements, unless the context clearly dictates otherwise.

The present invention can be significantly modified in its practice. Accordingly, the above description is not intended to be limiting, and the invention should not be construed as being limited to the specific examples described above.

Claims (38)

Except for the carbon atoms that form the perimeter of the graphene layer of the nanoplatelet, including the graphene layer, (i) there are no elements or components other than sp ² carbon. And (ii) a substantially defect-free graphene layer, characterized in that the total content of halogen in the nano-plate is calculated as bromine, and that of the nano-plate About 5% by weight or less, based on the total weight of the grafted nano-particles. The halogenated graphene nanofabric article of claim 1 having a halogen chemically bonded around the graphene layer of the nanofabric. The halogenated graphene nanofabric sheet according to any one of claims 1 to 3, which is a brominated graphene nanoplate having bromine chemically bonded around a graphene layer of a nano plate. The brominated graphene nanoparticle as claimed in claim 3, having improved dispersibility in water. The halogenated graphene nanofabric body according to claim 1, wherein the nanofabric body is a brominated graphene nanofiber. 6. The brominated graphene nanofabric article of claim 5, wherein the nanofabric has a total bromine content in the range of about 0.001 wt% to about 5 wt%, based on the total weight of the nanofibrous substrate. 6. The brominated graphene nanofabric article of claim 5, wherein the nanofabric comprises a few-layered graphene. 6. The brominated graphene nanofabric article of claim 5, wherein the nanofibrous body comprises a two-layered graphene. The brominated graphene nanofibrous body according to claim 7 or 8, wherein the nanofabric has a distance between the layers of about 0.335 nm when measured by high resolution transmission electron microscopy. The brominated graphene nanofabric article according to claim 5 or 9, wherein said nanofabric body comprises two-layer graphene having a thickness of about 0.7 nm when measured by atomic force microscopy. 7. The brominated graphene nanofibrous body according to claim 5 or 6, wherein the brominated graphene nanofibrous body exhibits negligible weight loss when performing thermogravimetric analysis at a temperature of about 800 DEG C or less under an inert atmosphere. The brominated graphene nanofabric article of claim 5 or 6, wherein the brominated graphene nanofibrous body exhibits a weight loss of less than or equal to about 4 weight percent when performing thermogravimetric analysis at about 900 DEG C under an inert atmosphere. 6. The brominated graphene nanofabric article of claim 5, having a lateral size in the range of about 0.1 to about 50 microns when measured by atomic force microscopy. 14. A halogenated graphene nanofibrous body according to any one of claims 1 to 13, having undetectable chemically bonded oxygen impurities. Halogenated exfoliated graphite having a total halogen content of about 5% by weight or less, based on the total weight of the halogenated exfoliated graphite as calculated as bromine. A method for producing halogenated exfoliated graphite in the absence of water and oxygen,
I) contacting a binary halogen selected from a bromine element, a fluorine element, iodine monochloride, iodine monobromide, iodine monofluoride, and a mixture of any two or more thereof with a graphite flake to form a halogen- To form a solid comprising graphite; And
II) A process for the preparation of halogen-intercalated graphite, comprising the steps of: (a) rapidly heating halogen-intercalated graphite to a temperature above about 400 ° C,
(b) contacting the divalent halogen selected from Br ₂ , F ₂ , IC 1, IBr, IF, or a mixture of any two or more thereof in a reaction zone in the absence of oxygen and water vapor, with halogen- Lt; / RTI >
In the reaction zone where oxygen and water vapor are not present, halogen-intercalated graphite is fed,
Withdrawing halogenated exfoliated graphite from the reaction zone,
The halogenated exfoliated graphite having a total halogen content of about 5 weight percent or less based on the total weight of the halogenated exfoliated graphite when calculated as bromine; And
III) optionally, repeating step I) and step II) one or more times in order. 17. The method of claim 16,
IV) treating the halogenated exfoliated graphite with a halogenated graphene nanofabric glass procedure to form a halogenated graphene nanofibrous body; And
V) optionally further comprising repeating step I), step II) and, optionally, step IV) one or more times in order. 17. The method of claim 16, wherein the halogen-intercalated graphite is formed in a fluidized bed. The method of claim 16, wherein the halogenated exfoliated graphite produced thereby has a total halogen content in the range of from about 0.001 wt% to about 5 wt% when calculated as bromine, based on the total weight of the halogenated exfoliated graphite . 18. The method of claim 17, wherein the halogenated graphene nanoparticles produced thereby yield a total halogen content in the range of about 0.001 wt.% To about 5 wt.%, Calculated as bromine, based on the total weight of the nanoplate / RTI > 20. The method according to any one of claims 16 to 19, wherein the graphite flakes have a lateral dimension of at least about 50 microns. 21. The method according to any one of claims 16 to 20, wherein the divalent halogen used in the method is a bromine element. 23. The method according to any one of claims 16 to 22, wherein the method is carried out as a continuous process. 23. The method according to any one of claims 16 to 22, wherein the method is performed as a batch process. An energy storage device comprising an electrode consisting of a halogenated graphene nanofabric body, wherein the nanofibrous body comprises a graphene layer and comprises: (i) a carbon nanotube- a graphene layer in which no element or component other than sp ² carbon is present, and (ii) a substantially defect-free graphene layer, wherein the total content of halogens in the nano plate is calculated as the total weight of the nano- By weight based on the total weight of the energy storage device. 26. The energy storage device of claim 25, wherein the energy storage device is a lithium ion battery, a lithium sulfur battery, a lithium air battery, a lithium ion capacitor, a supercapacitor, a sodium ion battery, or a magnesium ion battery. 26. The energy storage device of claim 25, wherein the electrode is an anode. 28. The energy storage device of claim 27, wherein the anode is a silicon anode. 26. The method of claim 25, wherein the electrode is an anode or cathode containing carbon black, wherein the brominated graphene nanofibrous body comprises at least about 0.1% by weight, based on the total weight of the carbon black at the anode or cathode, An energy storage device comprising carbon black at the cathode. 26. The energy storage device of claim 25, wherein the electrode is a cathode. 26. The energy storage device of claim 25, wherein the energy storage device comprises a solid state electrolyte. 28. The method of claim 27,
A material selected from carbon, silicon, and / or one or more silicon oxides;
bookbinder;
A conductive aid;
Carbon black; And
The energy storage device comprising at least one of the collectors. 33. The energy storage device according to any one of claims 25 to 32, wherein the halogenated graphene nano plate is a brominated graphene nanofiber. A thermoplastic or thermoset composition comprising from about 0.1 to about 30 weight percent of a halogenated graphene nanofibrous body, wherein the halogenated graphene nanofibrous body comprises a graphene layer and the periphery of the graphene layer of the nano- (I) a graphene layer in which no elements or components other than the sp ² carbon are present, and (ii) a substantially defect-free graphene layer, except for the carbon atoms that form. 35. The composition of claim 34, wherein the halogenated graphene nanoparticle is a brominated graphene nanocrystal. A lubricant composition comprising a halogenated graphene nanofabric body, wherein the halogenated graphene nanofibrous body comprises a graphene layer and comprises: (i) a carbon nanotube- a graphene layer in which no elements or components other than sp ² carbon are present, and (ii) a substantially defect-free graphene layer. A catalyst system comprising a halogenated graphene nanofabric body, wherein the halogenated graphene nanofibrous body comprises a graphene layer and comprises: (i) a carbon nanotube- a graphene layer in which no elements or components other than sp ² carbon are present, and (ii) a substantially defect-free graphene layer. 38. The catalyst system according to claim 37, wherein the halogenated graphene nanofibrous body is used as a carbocatalyst, in a metal-free catalysis, in a photocatalytic action, or as a catalyst support.

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